Diapositivo 1
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Index Preface ..………………………………….………………………………………. Page 3 The archipelago of the Azores ……………………………………….. Page 4 Characteristics of the Cetaceans ……………………………………. Page 5 Cetaceans classification ..……………………………………………….. Page 6 Whale hunting …………………………………………………………………. Page 7 Species ……………………………………………………………………………. Page 8 Other languages ……………………………………………………………… Page 47 The ocean and you …………………………………………………………. Page 49 Acknowledgements …………………………………………………………. Page 50 2 Preface A whale watching trip in the archipelago of the Azores, is a unique and amazing experience. It is possible to interact with cetaceans and other animals in their natural environment by seeing, getting a feeling of closeness and enjoying their behavior. It is possible to observe many different species of animals, not only cetaceans, but also birds, fish, sharks and others. The aims of this Ocean Guide are to summarize the most important species seen on these trips, giving important information and additional details that might be interesting, as well as providing representative images. It is not supposed to be a very technical guide but a tool that can Through this guide, everyone will get the chance to easily be used by any person, and consider and appreciate the unquestionable beauty that can be useful for identifying and and see how fascinating these marvelous animals are. learning about the species viewed during the trip. 3 The archipelago of Azores Located in the middle of the North Atlantic, the archipelago of the Azores is one of the best sites in Europe for the observation of Cetaceans. The nine Azorean islands are the most visible faces of a complex set of underwater mountains with over a thousand meters in depth, created by volcanic activity, due to the tectonic movements of the Eurasian plate, the African plate and the North American plate. Very few places in the world have the specific conditions which make this group of islands one of the most interesting places for Whale Watching. The whales, with special focus on the Sperm whales, get close to the islands of São Miguel and Pico thanks to the morphology of the sea bottom, the depth, the currents and hence, the abundance of food. When the deep sea nutrient- rich currents encounters an island a phenomenon called the “island mass effect” occurs, where basically this deep sea currents are forced to go up, enriching the surface waters. All year-round it is possible to see pods of sperm whales and many different species of dolphins. In spring, it is also possible to see different species of large baleen whales. 4 Characteristics of the Cetaceans When we talk about cetaceans, what we are actually doing, is talking about mammals. Dolphins, whales, beaked whales and porpoise are all marine mammals. As mammals, they present typical features from this groups: - They are warm-blooded animals (endothermic) - They have mammary (milk-secreting) glands hidden in a slit within their belly Echolocation - They present hair at birth - Breathing with lungs (impossible to breathe As cetaceans, they present some special under the water) features: - Completely adapted to the aquatic life (streamlined body; extremities modified to fins; strong horizontal tail…) - Ribs not joined at the sternum (more lung capacity) - Nostrils moved to the top of the head (one blowhole in the Odontoceti; two blowholes in the Mysticeti) - Echolocation (they emit a sound which Odontoceti Mysticeti bounces off an object and returns, giving information about the size, distance) - Thick layer of oil and fat called blubber under the skin - Lost of sebaceous (fat-secreting) and exocrine (sweat) glands. 5 Cetaceans classification Cetaceans are divided into two main groups (Suborders): Odontoceti or toothed cetaceans, which includes dolphins, sperm whales, beaked whales and porpoises, and Mysticeti or baleen cetaceans consisting of the baleen whales. Odontoceti Mysticeti Baleen plate The Odontoceti have equaly sized and shaped teeth, and they feed on small schooling fish, squid, crustaceans. The Mysticeti include 11 different species. The baleen plates are located on the upper jaw, and they are used for feeding. One of the feeding methods consists of a large quantity of water and food (krill, plankton, small fish…) entering the whale’s mouth then closing it and using their tongue, they push the water against the baleen plates. Water exits, but the food is retained. 6 Whale hunting The whale hunting was a really important activity in the Azores. It started in the second half of the 18th century, and it was not until 1987 that it was forbidden, due to ecological pressures and the depreciation of the whaling industry. It became an opportunity for people as an extra economic support. During this time, the cetaceans, especially the sperm whale, were extremely hunted. But actually, everything was useful and nothing was wasted. They obtained oils, cosmetics, fertilizers and other products that generated a lot of money. “Look-outs” were people that worked based on-land observing the ocean. They were strategically located, with really good views, and they used high visibility binoculars for spotting the animals. It is actually the same strategy people use for finding animals in whale watching. In the Azores there has been a peaceful transition from hunting to whale watching. Nowadays, no one even dares to think about going back to the time when whales were killed for commercial purposes. Unfortunately, in some countries, this is now a subject being discussed and is slowly gaining supporters. 7 Species Cetaceans ………………………………………………………………………… Page 9 Birds ………………………………………………………………………………... Page 30 Sea Turtles ………………………………………………………………………. Page 37 Fish ………………………………………………………………………………….. Page 39 Jellyfish ……………………………………………………………………………. Page 46 8 (PT: Baleia azul/ UK: Blue whale/ DE: Blauwal/ SE: Blåval/ ES: Ballena azul/ FI: Sinivalas) The blue whale is the biggest existing animal, reaching up to 30 m long (the largest animal known to date measured 33 Average length: 26–30 m m). It might be easily confused with the fin whale or the sei whale, so its size and its Average weight: 100–160 T (heaviest one 190 T) small dorsal fin can help to identify it with more accuracy. Feeding on: small invertebrates (mainly krill) The body coloration is gray with lighter spots spread all over the body. Their head Periodicity: Seasonal species (Spring and Autumn) is flat in front of the blowholes. When it blows, it can reach 12 m high. Their baleen plates, where they retain their food (krill), can reach up to 1 m long and 55 cm wide, being the largest among all the Mysticeti. Newborns measure 7 m and they weigh 6 to 7 tons. Females bear a single calf every 2 to 3 years. Gestation lasts about 1 year and lactation takes at least 7 months. It can live up to 80-90 years. These animals can dive up to a depth of 200 m (for 30 min) and cruises at a maximum speed of 40 km/h. They do not stay long in the Azorean waters, but they are observed offshore the islands during migration. 9 (PT: Baleia comum/ UK: Fin whale/ DE: Finnwal/ SE: Sillval/ ES: Rorcal común/ FI: Sillivalas) The fin whale is the second largest animal existing in the world (22 m). His body is dark gray on the upper part Maximum length: 21 m (males) / 26 m (females) and white on the ventral region. Also, the lower right jaw is white, while the lower left jaw is light gray. Maximum weight: 80 T They make long migrations. During summer, they remain in high latitudes Feeding on: Fishes and small cephalopods where they feed on small fishes, small cephalopods and small crustaceans, like Periodicity: Seasonal species (from March to July) krill, which are retained in their baleen plates. However, in winter, they migrate to tropical regions where they breed. Gestation lasts for about 1 year and lactation takes at least 6 months. Newborns measure about 6 m long and 2 or 3 T weight. Each female can bear a calf every 2 or 3 years. It is thought that they live up to be 80-90 years and they can swim up to 40 km/h. They can emit several types of sounds, heard up to hundreds of kilometers away. They usually live in groups of 2-5 members. 10 (PT: Baleia sardinheira/ UK: Sei whale/ DE: Seiwal/ SE: Sejval/ ES: Rorcual norteño/ FI: Seitivalas) The Sei whale is the fastest existent whale, reaching speeds Maximum length: males 17 m / females 20 m of 55 km/h! The body is gray on the back and Average weight: 20 to 30 T sides and has a lighter coloration on the ventral region. It has 32- 62 grooves, all ending before the Feeding on: Small planktonic crustaceans, small navel. fishes (harenk or sardines) and squid. They have 320-340 baleen plates, which can measure up to Periodicity: Mainly in summer 80 cm long. The Portuguese name “ baleia sardinheira” is due to the fact that they usually feed on sardines, among other species of schooling fish. It can dive at depths of more than 300 m for periods of 5-20 min. Newborns measure 4,5 m and weigh up to 1 T. Females bear a single calf every 3 to 4 years. Gestation lasts about 1 year, and lactation takes about 6 to 9 months. The Sei whale can live for up to 70 years. 11 (PT: Baleia-anã/ UK: Minke whale/ DE: Zwergwal/ SE: Vikval/ ES: Rorcual aliblanco/ FI: Lahtivalas) This whale is the smallest one among all the baleen whales. The body is dark gray on the back, and Maximum length: 8 m (males) / 9,5 m (females) light gray and white on each side of the body. The blow is low and difficult to Average weight: 5-10 T detect. There are some ways to distinguish them: an acutely head that emerges Feeding on: primarly on small fish (such as harenks or sardines), first out of the water allowing the and krill as well observation of the baleen plates, a skin without scars and distinctive white Periodicity: Rare species bands on the flippers.